title: Synthesis of stable silicon heterocycles by reaction of organic substrates with a chlorosilylene [PhC(NtBu)2SiCl].
abstract: Heteroleptic chlorosilylene (PhC(NtBu)(2)SiCl) (1) reacts with unsaturated organic compounds under oxidative addition. Reactions of 1 with cyclooctatetraene (COT) and a diimine afford [1+4]-cycloaddition products 3 and 6, respectively. In the case of COT, one Si-N bond of the amidinato ligand is cleaved, resulting in tetracoordinate silicon, whereas with a diimine a pentacoordinate silicon is formed. Treatment of 1 with ArN=C=NAr (Ar=2,6-iPr(2)C(6)H(3)) yields silaimine complex 4 with cleavage of one of the C=N bonds. The facile isolation of silaimine complexes is probably due to the kinetic protection afforded by the bulky Ar moiety. When 1 is treated with tert-butyl isocyanate, cleavage of the C=O bond is observed, which leads to formation of the four-membered Si(2)O(2) cycle 5. The same product is formed when 1 is allowed to react with trimethylamine N-oxide. When 1 is treated with diphenyl disulfide, cleavage of the S-S bond occurs to form 7. All products have been characterized by multinuclear NMR spectroscopy, EI mass spectrometry, and elemental analysis. In addition, the molecular structures of 3-6 have been determined by single-crystal X-ray diffraction studies. Collectively, these results suggest that owing to the presence of the lone pair of electrons, the propensity of 1 to undergo oxidative addition is very high.
authors.affiliation: Institute of Inorganic Chemistry, Tammannstrasse 4, 37077 Göttingen, Germany.
authors.forename: Shabana
authors.initials: S
authors.lastname: Khan
authors.forename: Sakya S
authors.initials: SS
authors.lastname: Sen
authors.forename: Daniel
authors.initials: D
authors.lastname: Kratzert
authors.forename: Gašper
authors.initials: G
authors.lastname: Tavčar
authors.forename: Herbert W
authors.initials: HW
authors.lastname: Roesky
authors.forename: Dietmar
authors.initials: D
authors.lastname: Stalke